Shouldn’t a TCP upload work without error or retransmit if there is an error? UDP has the potential to drop the packet but TCP has the error correction built into the communication (ironically that’s exactly what I am trying to do today and making sure the data gets there is critical to my sanity).
I believe you are correct for the TCP vs UDP difference. However, a situation can occur where my particle looses cellular connection for an extended period of time. I have the program set to continue operating in these conditions. from what I have seen so far, after trying 5 times TCP will eventually stop trying. If my device keeps running, I’ll keep having data points to upload later when cellular connection resumes.